<template>
  <div class="alert">
    <div class="alert-main" v-for="item in notices" :key="item.name">
      <div class="alert-content">{{item.content}}</div>
    </div>
  </div>
</template>
<script>
let seed = 0;
function getUid(){
  return 'alert_' + (seed++)
}
export default {
  data() {
    return {
      notices: []
    };
  },
  methods: {
    add(notice){
      const name = getUid();
      let _notice = Object.assign({
        name
      }, notice)

      this.notices.push(_notice)
      // duration获取notice的时间长度
      const duration = notice.duration
      setTimeout(() => {
        this.remove(name)
      }, duration * 1000)
    },
    remove(name){
      const notices = this.notices;
      for(let i = 0; i< notices.length;i++){
        if(notices[i].name === name){
          this.notices.splice(i, 1);
          break;
        }
      }
    }
  }
};
</script>
<style>
.alert {
  position: fixed;
  top: 16px;
  width: 100%;
  left: 0;
  text-align: center;
  pointer-events: none;
}
.alert-content {
  display: inline-block;
  padding: 8px 16px;
  background: #fff;
  border-radius: 3px;
  box-shadow: 0 1px 6px rgba(0, 0, 0, 0.2);
  margin-bottom: 8px;
}
</style>